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    <title>Nim by Example - If, Else, While</title>

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<article>
    <h1 id="if-else-while">If, Else, While</h1>

    <p>Nim has many different control flow constructs, including the standard <code>if</code>s, <code>else</code>s, and
        <code>while</code>s. However, Nim does not use an <code>else if</code> construct like many languages, it uses a
        more condensed <code>elif</code>.</p>

    <p>When inside a loop, <code>continue</code> can be used to skip the rest of the loop body and to begin the next
        iteration; <code>break</code> can be used to immediately leave the loop body.</p>

    <p>Along with <a href="../block">its other uses</a>, the <code>block</code> statement can be used to create a label
        so that it’s possible to break out of nested loops.</p>

    <!--skip-->
    <pre><code class="language-nim"><span class="kn">import</span> <span class="n">strutils</span><span
            class="p">,</span> <span class="n">random</span>

<span class="n">randomize</span><span class="p">()</span>
<span class="k">let</span> <span class="n">answer</span> <span class="o">=</span> <span class="n">rand</span><span
                class="p">(</span><span class="mi">10</span><span class="p">)</span>
<span class="k">while</span> <span class="kp">true</span><span class="p">:</span>
  <span class="n">echo</span> <span class="s">"I have a number from 1 to 10, what is it? "</span>
  <span class="k">let</span> <span class="n">guess</span> <span class="o">=</span> <span class="n">parseInt</span><span
                class="p">(</span><span class="n">stdin</span><span class="p">.</span><span
                class="n">readLine</span><span class="p">)</span>

  <span class="k">if</span> <span class="n">guess</span> <span class="o">&lt;</span> <span class="n">answer</span><span
                class="p">:</span>
    <span class="n">echo</span> <span class="s">"Too low, try again"</span>
  <span class="k">elif</span> <span class="n">guess</span> <span class="o">&gt;</span> <span
                class="n">answer</span><span class="p">:</span>
    <span class="n">echo</span> <span class="s">"Too high, try again"</span>
  <span class="k">else</span><span class="p">:</span>
    <span class="n">echo</span> <span class="s">"Correct!"</span>
    <span class="k">break</span>

<span class="k">block</span> <span class="n">busyloops</span><span class="p">:</span>
  <span class="k">while</span> <span class="kp">true</span><span class="p">:</span>
    <span class="k">while</span> <span class="kp">true</span><span class="p">:</span>
      <span class="k">break</span> <span class="n">busyloops</span></code></pre>

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